Nasturtiums and marigolds are popular annual flowering plants that bring color and vibrancy to gardens. Appreciated for their ornamental appeal, their ease of growth makes them a favorite among gardeners. They are suitable for various garden designs, whether planted in beds, borders, or containers.
Nasturtiums Characteristics and Uses
Nasturtiums, known as Tropaeolum, are distinguished by their nearly circular, lily-pad-like leaves. Their flowers bloom in shades of yellow, orange, and red, often funnel-shaped with a long spur. These plants exhibit two growth habits: bushy, compact forms and vining or trailing types that can spread as groundcover or climb with support.
Nasturtiums are edible; the leaves, flowers, and immature seedpods offer a peppery, mustard-like flavor. They are used to add a zesty taste and colorful garnish to salads. Nasturtiums attract beneficial pollinators such as bees, butterflies, and hummingbirds to the garden. They also draw certain pests, like aphids, to themselves.
Marigolds Characteristics and Uses
Marigolds are recognized for their bright blooms in shades of yellow, orange, and red. Their flowers can take various forms, from pom-pom-like to daisy-shaped, and their foliage is often finely cut with a strong scent. Common types include African marigolds, known for their large, double flowers, and French marigolds, which are more compact with smaller blooms.
Marigolds are valued in gardens for their pest-deterring qualities. Their strong scent repels various insects. Certain varieties, particularly French marigolds, are effective against nematodes, microscopic worms that damage plant roots. Marigold roots release compounds like alpha-terthienyl that inhibit nematode development. These plants are often incorporated into vegetable gardens to protect crops.
Cultivating Nasturtiums and Marigolds
Both nasturtiums and marigolds are easy to grow and thrive under similar conditions, making them suitable companions. They prefer a location that receives full sun, meaning at least six hours of direct sunlight daily, to encourage abundant flowering. They can tolerate some partial shade, especially in hotter climates, though bloom production may be reduced.
Well-drained soil is important for both plants, as they are susceptible to root rot in waterlogged conditions. Nasturtiums prefer poorer soils and do not require additional fertilizer, as rich soil can lead to more foliage growth at the expense of flowers. Marigolds also do not require heavy feeding; incorporating organic matter like compost into the soil before planting is sufficient. Both plants benefit from consistent, moderate watering, allowing the soil to dry out slightly between waterings. Water at the base of the plant to prevent fungal issues on the foliage.
Companion Planting Benefits
Planting nasturtiums and marigolds together, or near other garden plants, enhances the overall health of the garden ecosystem. Nasturtiums function as a “trap crop” for aphids. Aphids are highly attracted to nasturtiums and will congregate on these plants, diverting them from vulnerable vegetables like cabbage, lettuce, or beans. This concentration allows gardeners to manage infestations more easily, by removing affected plants or treating them directly. Nasturtiums also attract beneficial insects like hoverflies and ladybugs, which prey on aphids, aiding pest control.
Marigolds contribute to soil health and pest deterrence through their root secretions. French marigolds, in particular, release compounds from their roots that are toxic to root-knot nematodes, microscopic soil-borne pests that damage the roots of many vegetable crops like tomatoes, potatoes, and beans. For maximum effectiveness, marigolds should be planted where the target crop will grow, ideally for a period before the main crop, as the nematicidal effect takes time to establish. The strong scent of marigold foliage can also deter other above-ground pests. When planted together, nasturtiums manage above-ground aphid populations, while marigolds combat nematodes below the soil, providing comprehensive pest management.